The present invention relates to a casing bottom for a propelling charge casing. More particularly, the present invention relates to such a casing bottom which has a circular ring-shaped (annular) base plate provided with a centrally arranged primer sleeve for accommodating a primer element and with a cylindrical section at the outer edge of the base plate and formed in one piece with the base plate.
Propelling charge casings are usually provided with a casing bottom that has a planar base plate and, in large-caliber ammunition, for example, for armored weapons, is composed of high strength steel because of the high gas pressures occurring upon firing (approximately 7000 bar for 120 caliber and about 8000 bar for 140 caliber ammunition). The forged casing bottom blank is given a machining pretreatment, is then further tempered by a special heat treatment and finally machined again. Then it is surface treated in order to ensure corrosion protection and finally a rubber sealing lip is vulcanized on. This is a very expensive manufacturing process.